A massive spike in insulin prices is causing a health crisis for millions of diabetes patients who depend on the lifesaving drug, doctors say. Now, after years of rapid increases having nothing to do with available supply and not matched elsewhere in the world, those in the U.S. insulin supply chain are blaming each other. Tens of thousands of medical professionals are engaged in an intricate therapeutic ballet performed to protect the health, limbs, and lives of the almost 30 million people in the U.S. suffering from diabetes.